What is the right size bike for me?

Because people have different inseam lengths and bicycles vary in frame geometry from brand to brand, I suggest going to your local bicycle store and asking them, but here is start:

For an approximate road bike frame size, you can multiply your inseam length by 0.68, this should provide 4 to 5” of exposed seat post when your saddle is at the correct height. You can check for proper fit by standing over the “top tube” with your feet 6” from the center of the bike. You should have about 1 to 3” between the top tube and your groin. Road bike sizes are usually measured in centimeters (48, 50, 52, 54, 56, 58, 60 and 62cm). Just to give you an idea of what to expect, a cyclist who is 5’ 10’’ needs about a 54cm road bike. For an approximate mountain bike frame size, subtract 10 to 12 cm from your road bike size.